Pretty much all new chainsaws are self lubricating when it comes to bar and chain, so usually all you need to do is check and refill the tank on a regular basis.
N.B. Automatic or not, checking and refilling the tank are vital parts of chainsaw maintenance so try to get into the habit of checking before every use, this way you will avoid over heating and damage.
For manual lubrication, these days the only the part you are likely to do manually is the nose sprocket if your saw has one.
The sprocket is lubricated by pumping your lubricant of choice into the small grease hole at the tip of your saw. (See the image below)
Try to use, as Stihl put it "an environmentally compatible quality chain and bar lubricant with non-fling additive".
N.B. The service life of both the the chain and the guide bar are affected by the type and quality of your chosen lubricant, so do try not to just use old cooking oil!